1. Field of the Invention
The present invention relates to a reproducing apparatus, and more particularly to a voice selecting circuit capable of varying in accordance with the input level to a microphone the mixing level of a vocal plus instrument part and an instrumental part without vocal which parts are reproduced from a recording medium in which the two parts are separately recorded.
2. Prior Art
A KARAOKE is an apparatus that radiates through a loudspeaker the accompaniment for a song reproduced from a recording medium and the user's vocal when the sings that song toward a microphone to the accompaniment. The user can enjoy singing a song just like a professional singer who sings to a professional orchestra behind. A conventional KARAOKE apparatus is provided with a voice selecting function or vocal selecting function in which when a user sings a tune, the accompaniment for that tune reproduced from a recording medium such as a disc and a magnetic tape is outputted together with the user's voice or vocal inputted through the microphone, and the accompaniment reproduced and the vocal part by a professional singer recorded are both outputted when the user fails to sing toward the microphone.
Utilizing this arrangement, the user can enjoy singing to the accompaniment as in an ordinary KARAOKE apparatus while also preventing a drawback that only the accompaniment is radiated when the user suddenly forgets the words while he is singing.
FIG. 7 shows a conventional voice selecting circuit. A microphone 1 picks up the voice of the user and outputs the voice signal to an amplifier 2. The output of the amplifier 2 is supplied to a rectifier circuit 31 by which the voice signal is converted into a dc voltage. A comparator 32 compares the dc voltage outputted from the rectifier circuit 31 with a predetermined reference voltage to provide an output. The rectifier circuit 31 and the comparator 32 forms an audio detection circuit 3. Specifically, the comparator provides an L level when the voice input is less than a predetermined level and an H level when the input is more than the predetermined level. A reproducing apparatus 5 reproduces the accompaniment of a selected tune as well as the accompaniment plus vocal part by a professional singer. The recording medium in the reproducing apparatus 5 is a so-called voice multiplex tape or voice multiplex disc in which only the accompaniment is recorded in one of L and R channels and the accompaniment plus vocal part by the professional singer in the other. Only the accompaniment is outputted from, for example, an L channel terminal 5L and the accompaniment plus vocal part by the professional singer from an R channel terminal 5R. A selector switch 4 selects the accompaniment outputted from the reproducing apparatus 5 when the signal from the comparator 32 is the H level and the accompaniment plus vocal when the signal is the L level.
The output of the selector switch 4 is supplied to a mixer circuit 6 which mixes the output from the selector switch 4 with the output of the amplifier 2 to provide thus mixed audio signal to a loudspeaker 7.
When the voice input level through the microphone 1 exceeds the predetermined level, for example, when the user is singing, the singing voice of the user and the accompaniment from the reproducing apparatus 5 are radiated from the loudspeaker 7. When the voice input level through the microphone is less than the predetermined level, for example, when the user stops to sing, the singing voice of the professional singer and the accompaniment from the reproducing apparatus 5 are radiated from the loudspeaker 7.
However, the aforementioned conventional voice selecting circuit suffers from a drawback that when the user's voice level drops to less than the predetermined level, the vocal part by the professional singer suddenly appears and therefore the audience feels uncomfortable.